The findings of this study contribute to our understanding of the sociodemographic characteristics associated with the use of breast and cervical cancer screening. Being married and having a higher education level, rural residence, and private health insurance were significantly associated with higher rates of breast and cervical cancer screening, after adjusting for age and sociodemographic factors. Household income was not significantly associated with mammograms or Pap smears.
Of the sociodemographic factors, household income was not shown to be significantly associated with mammograms or Pap smears by multivariate logistic regression after full adjustment. Other studies have suggested that household income affects mammogram and Pap smear participation, with women from low-income households less likely to participate than those from high-income households [2, 5, 19–21]. Inequalities in breast and cervical cancer screening still exist in the UK, despite free screening for the entire population . Many studies have suggested that having access to a physician who performs mammograms and Pap smears was a powerful predictor of breast and cervical cancer screening [2, 5, 21–26]. A possible cause of this difference in study results is that in 1999, Korea began screening for cancer as part of the NCSP, which covers the entire population. NCSP provides screening services free of charge for Medical Aid enrollees and NHI participants with a contribution below 50%. Since 2010, the NCSP has included a subsidy of 90% for people with NHI with a contribution over 50%. Such government support might have reduced the effect of household income on breast and cervical cancer screening participation [1, 18, 27].
Our finding of higher rates of having ever had a mammogram and Pap smear among women with a rural residence differs from the results of other studies that have indicated low rates among women with a rural residence [5, 23–25]. This may have resulted partly from the mobile screening service now provided by the NCSP. The mobile screening service is helpful for target populations who are not able to access medical institutions to obtain appropriate screening, and it may contribute to improving compliance with the screening program. The increase in the compliance rate for the cancer screening program might have resulted from the provision of accessible and acceptable screening services, such as mobile screening.
A disparity in mammogram and Pap smear use was found among women of different education levels after adjusting for age and sociodemographic factors. Other studies have used multivariate logistic regression analysis to show that women were more likely to undergo a mammogram and Pap smear if they had a higher education level [2, 5, 19–21]. To date, a low education level is a known barrier to breast and cervical cancer screening. Some studies have indicated that routine monitoring of coverage of screening and information polices affect breast and cervical cancer screening rates at various education levels [2, 18, 22, 24]. Additionally, the perception of not needing the test due to good health or an absence of symptoms was the most frequently reported barrier to participation in breast and cervical cancer screening in all age groups. Thus, we need to increase the knowledge and awareness of cancer in the target population to increase the participation rate in cancer screening programs [22, 24, 26, 28–30]. Attempts to promote cancer screening have used a public health model that targets entire communities, e.g., mass-media campaigns about the organized screening system in Korea. Additional individual-directed interventions in health care settings regarding cancer screening use are required, such as individualized in-person or telephone counseling, individualized letters and reminders, or other individual-directed strategies, to increase participation and reduce the disparity in cancer screening [18, 27, 30].
There may be other reasons for the low perceived risk of breast and cervical cancer in addition to perceptions of good health or an absence of symptoms. There could be no experience of cancer among friends and family, misperceptions about the causes of cancer, or not feeling at risk of cervical cancer because of sexual experience [22, 24, 25]. Alternative reasons could include the fact that the service offered is unattractive to women or promoted in an unattractive manner. However, we did not investigate these reasons in this study. We need to study these reasons further. The rate of not undergoing screening of breast and cervical cancer due to a lack of time was high in the women between 40 and 49 years old compared with other age groups. Officials are discussing whether to give a holiday for cancer screening or to provide cancer screening service at the employee's place of work while on duty.
Private health insurance was the strongest predictor of breast and cervical cancer screening. Koreans can take cancer screening through organized or opportunistic systems. Even if they can take cancer screening free of charge or for a small fee, which is only 10% of the cost, when they want to take organized cancer screening, some people prefer opportunistic screening to organized screening. In this case, having private health insurance is a necessary precondition for improving the use of cancer screening, because private health insurance can remove economic and practical barriers to screening in opportunistic settings .
This study has several limitations, based on the KNCSS data that we used. First, KNCSS data were self-reported, which may have introduced a bias because several studies have suggested that self-reports overestimate the prevalence of participation in cancer screening. Second, we were unable to explore the influence of other important correlates, such as test-specific characteristics (e.g., preparation, cost, time constraints, and transportation for screening) and psychological factors (e.g., discomfort, concern about complications, or anxiety about the procedure) involved in the use of breast and cervical cancer screening. Third, we focused on women who have ever had screening in this study. It is difficult to compare the life-time screening rates with screening rates with recommendations directly.